现在，所有这些代码都显示两个标记，一个位于当前位置，另一个位于指定的目标位置。我需要他们之间的路线。我已经在下面发布了我的MapsActivity的代码。我知道我们必须使用JSON和折线来完成工作，但不知道在哪里以及如何使用它们。
MapsActivity.java
package gcmojo.com.location;
import android.Manifest;
import android.content.IntentSender;
import android.content.pm.PackageManager;
import android.location.Geocoder;
import android.location.Location;
import android.os.AsyncTask;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.maps.model.PolylineOptions;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
public class MapsActivity extends FragmentActivity implements
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
public static final String TAG = MapsActivity.class.getSimpleName();
private final static int CONNECTION_FAILURE_RESOLUTION_REQUEST = 9000;
private GoogleApiClient mGoogleApiClient;
private LocationRequest mLocationRequest;
private GoogleMap mMap;
double currentLatitude;
double currentLongitude;
EditText loc;
String loca;
String country;
TextView myAddress;
/*text view for mentioning the destination*/
@
Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(10 * 1000) // 10 seconds, in milliseconds
.setFastestInterval(1 * 1000); // 1 second, in milliseconds
}
@
Override
protected void onResume() {
super.onResume();
setUpMapIfNeeded();
mGoogleApiClient.connect();
}
@
Override
protected void onPause() {
super.onPause();
super.onPause();
if (mGoogleApiClient.isConnected()) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
mGoogleApiClient.disconnect();
}
}
//method for current location
private void handleNewLocation(Location location) {
Log.d(TAG, location.toString());
double currentLatitude = location.getLatitude();
double currentLongitude = location.getLongitude();
LatLng latLng = new LatLng(currentLatitude, currentLongitude);
// mMap.addMarker(new MarkerOptions().position(new LatLng(currentLatitude, currentLongitude)).title(coun));
MarkerOptions options = new MarkerOptions()
.position(latLng)
.title(getCompleteAddressString(currentLatitude, currentLongitude));
mMap.addMarker(options);
float zoomLevel = (float) 15.0;
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng, zoomLevel));
}
//method for placing marker at destination via destination address
public void onClick(View view) {
loc = (EditText) findViewById(R.id.editText);
loca = loc.getText().toString();
List < android.location.Address > addressList = null;
if (loca != null || loca.equals("")) {
Geocoder gc = new Geocoder(this);
try {
addressList = gc.getFromLocationName(loca, 1);
} catch (IOException e) {
e.printStackTrace();
}
android.location.Address address = addressList.get(0);
LatLng ll = new LatLng(address.getLatitude(), address.getLongitude());
mMap.addMarker(new MarkerOptions().position(ll).title("YO"));
mMap.animateCamera(CameraUpdateFactory.newLatLng(ll));
}
}
private void setUpMapIfNeeded() {
if (mMap == null) {
// Try to obtain the map from the SupportMapFragment.
mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map))
.getMap();
// Check if we were successful in obtaining the map.
if (mMap != null) {
setUpMap();
}
}
}
private void setUpMap() {
mMap.addMarker(new MarkerOptions().position(new LatLng(0, 0)).title("Marker"));
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
mMap.setMyLocationEnabled(true);
}
@
Override
public void onConnected(@Nullable Bundle bundle) {
Log.i(TAG, "Location services connected.");
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if (location == null) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
} else {
handleNewLocation(location);
}
}
@
Override
public void onConnectionSuspended(int i) {
Log.i(TAG, "Location services suspended. Please reconnect.");
}
@
Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
if (connectionResult.hasResolution()) {
try {
// Start an Activity that tries to resolve the error
connectionResult.startResolutionForResult(this, CONNECTION_FAILURE_RESOLUTION_REQUEST);
} catch (IntentSender.SendIntentException e) {
e.printStackTrace();
}
} else {
Log.i(TAG, "Location services connection failed with code " + connectionResult.getErrorCode());
}
}
@
Override
public void onLocationChanged(Location location) {
}
private String getCompleteAddressString(double latitude, double longitude) {
String strAdd = "";
Geocoder geocoder = new Geocoder(this, Locale.getDefault());
try {
List < android.location.Address > addresses = geocoder
.getFromLocation(latitude, longitude, 1);
if (addresses != null) {
android.location.Address returnedAddress = addresses.get(0);
StringBuilder strReturnedAddress = new StringBuilder("");
for (int i = 0; i < returnedAddress.getMaxAddressLineIndex(); i++) {
strReturnedAddress
.append(returnedAddress.getAddressLine(i)).append(
"\n");
}
strAdd = strReturnedAddress.toString();
}
/* Log.w("My Current loction address", "" + strReturnedAddress.toString());
} else {
Log.w("My Current loction address", "No Address returned!");
} */
} catch (Exception e) {
e.printStackTrace();
// Log.w("My Current loction address", "Canont get Address!");
}
return strAdd;
}
}
答案 0 :(得分：0)
在您的app build.gradle中包含此内容
dependencies {
...
compile 'com.google.maps.android:android-maps-utils:0.4+'
}
此库具有PolyUtil类。我不知道你正在使用哪个Direction JSON解析器，但我很确定它将有一个函数可以返回编码的折线String。然后使用下面的编码字符串
public void drawPolyline (){
String polylinePoints = YourParser.getPolylinePoints();
List<LatLng> pointsList = PolyUtil.decode(points);
mMap.addPolyline(new PolylineOptions().width(30).color(android.R.color.black).addAll(pointsList));
}